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Updated: Jun 12, 2026

Cell Type-specific Gene Expression Profiling in the Mouse Liver
10:06

Cell Type-specific Gene Expression Profiling in the Mouse Liver

Published on: September 17, 2019

Tob1 is a constitutively expressed repressor of liver regeneration

Karen J Ho1, Nhue L Do, Hasan H Otu

  • 1Department of Surgery, the Transplant Institute, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA.

The Journal of Experimental Medicine
|June 2, 2010
PubMed

Insights

Transducer of ErbB2.1 (Tob1), an inhibitory molecule, controls liver regeneration. Its down-regulation is essential for liver regrowth after injury, highlighting Tob1 as a key checkpoint.

Area of Science:

  • Hepatology
  • Molecular Biology
  • Cell Cycle Regulation

Background:

  • Liver regeneration involves complex signaling pathways.
  • Antiproliferative factors' roles in liver repair are not fully understood.
  • Transducer of ErbB2.1 (Tob1) is a known mito-inhibitory molecule.

Purpose of the Study:

  • To investigate the role of Tob1 in liver regeneration.
  • To determine how Tob1 levels influence hepatocyte proliferation.
  • To identify Tob1 as a potential checkpoint in liver repair.

Main Methods:

  • Screening for antiproliferative factors after liver injury.
  • Analyzing Tob1 protein levels post-hepatectomy in mice.
  • Evaluating hepatocyte proliferation in Tob1-deleted mice.
  • Investigating Tob1 interactions with cell cycle proteins (e.g., Cdk1).
  • Assessing Tob1's impact on gene transcription (E2F, p53 signaling).

Main Results:

  • Tob1 protein levels decrease after partial hepatectomy via posttranscriptional mechanisms.
  • Tob1 deletion enhances hepatocyte proliferation and accelerates liver mass restoration.
  • Tob1 down-regulation is necessary for normal liver regeneration.
  • Tob1 directly interacts with Caf1 and Cdk1, modulating Cdk1 activity.
  • Tob1 influences the transcription of key cell cycle genes.

Conclusions:

  • Tob1 acts as a crucial checkpoint molecule in liver regeneration.
  • Tob1 levels directly control the rate of liver regeneration.
  • Modulation of Tob1 impacts hepatocyte proliferation and cell cycle protein activity.

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